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3.2 Defining Services

3.2.1 <service>: Service Definition element

The XML element is used to define a service.

The attributes are described in more detail in the table below.

Attribute Description

uuid

Universally Unique IDentifier. The UUID uniquely identifies a service. 16-bit values are used for

the services defined by the and 128-bit UUIDs are used for manufacturer specific

Bluetooth SIG

implementations.

Options:

0000 to 16-bit UUIDs are reserved for the services standardized by the and FFFF:

Bluetooth SIG

must not be used for vendor specific implementations.

00000000-0000-0000-0000-000000000000 to FFFFFFFF-FFFF-FFFF-FFFF-FFFFFFFFFFFF:

128-bit UUIDs are reserved for vendor specific implementations.

The ID is used to identify a service within the service database and can be used as a reference

from other services (include statement below). This ID is not stored in the GATT database and a t

the moment it does not have other practical uses in BLE products. In BT121 this ID is also used

to generate an handle (and a constant revealed in the file) to be used with the new constants

. The ID can be used in the application code

dumo_cmd_gatt_server_set_service_status

(BGScript) to manage the service instead of using its handle number. Every service must use a

unique ID.

Value:

Any UTF-8 string

type

The type field defines whether the service is a or a service. Typically this primary secondary

does not need to be used.

If not defined, the value of this attribute will default to

type="primary"

advertise

This option can be used to include the service UUID in the advertisement packet payload.

Up to eight 16-bit UUIDs or one 128-bit UUID will fit into the advertisement data of BLE firmware.

Up to thirteen 16-bit UUIDs or one 128-bit UUID will fit into the advertisement data of BT121

firmware.

Note: you can use custom advertisements with the dedicated BGAPI/BGScript configuration

commands, in which case this option will not be valid.

Options:

true : UUID is included in advertisement data

false : UUID is not included in advertisement data (default)

NOTE! Service with attribute set to must be placed in one of the 8 first services

advertise "true"

of the gatt.xml tree.